cable internet sharing

I have cable modem hooked up to a WIN ME computer. It is connected through a motorola surf board sb4100 modem. The question is I have two other computers I want to hook up on the home network, so they can all share the Internet connection. I have a Linksys router I use now to connect all the computers through my dsl. I tried to just plug the cable modem into the uplink and get the connection that way, but it does not work, but it did with the dsl. I have WIN XP on one of the computers and the other two have ME. what do I need to do to have them all running and sharing the Internet?